Electrostatic operation device

Abstract

An electrostatic operation device in which a variation in the amount of electric charges accumulated in an electret film caused by physical impact can be suppressed. The electrostatic operation device (electrostatic induction power generating device ( 1 )) comprises movable electrodes ( 8 ), an electret film ( 5 ) so formed as to face the movable electrodes ( 8 ) at a space therebetween, and a stopper ( 401 b ) for suppressing the approach of the movable electrodes ( 8 ) to the electret film ( 5 ) within a predetermined space.

The invention claimed is: 
     
       1. An electrostatic power generating device comprising:
 a substrate; 
 a first electrode formed on a surface of said substrate; 
 a second electrode and an electret film so formed as to be opposed to said first electrode at an interval therebetween; and 
 a member inhibiting said first electrode and said electret film from moving close to each other within a prescribed interval, wherein 
 said electrostatic power generating device generates an electric power 
 when at least one of said first electrode and said electret film moves in a direction parallel to the longitudinal direction of said substrate and a relative distance between said first electrode and said electret film changes, 
 said first electrode is interposed between said substrate and said electret film, 
 said member is held by one of said substrate or said second electrode, 
 said second electrode has a groove shaped recess portion and projecting portion provided on a surface of said second electrode, and 
 said electret film is so formed as to be embedded on a bottom surface of said recess portion of said second electrode and said electret film is not formed on a surface of said projecting portion. 
 
     
     
       2. The electrostatic power generating device according to  claim 1 , wherein
 said electret film is formed on the bottom surface of said recess portion to have a thickness smaller than a depth of said recess portion. 
 
     
     
       3. The electrostatic power generating device according to  claim 1 , wherein
 said electret film formed to be embedded in said groove shaped recess portion is oblongly formed in plan view. 
 
     
     
       4. An electrostatic power generating device comprising:
 a substrate; 
 a first electrode formed on a surface of said substrate; 
 a second electrode and an electret film so formed as to be opposed to said first electrode at an interval therebetween; and 
 a member inhibiting said first electrode and said electret film from moving close to each other within a prescribed interval, wherein 
 said electrostatic power generating device generates an electric power when a relative position of said first electrode and said electret film moves at least in a horizontal direction, 
 said member is held by one of said substrate or said second electrode, 
 said second electrode has a groove shaped recess portion and projecting portion provided on a surface of said second electrode, and 
 said electret film is so formed as to be embedded on a bottom surface of said recess portion of said second electrode and said electret film is not formed on a surface of said projecting portion, 
 wherein said member is formed only on a surface of said projecting portion of said second electrode. 
 
     
     
       5. The electrostatic power generating device according to  claim 1 , wherein said first electrode comprises a plurality of electrodes. 
     
     
       6. The electrostatic power generating device according to  claim 1 , wherein said electret film comprises a plurality of electret portions.